This invention relates to a method of establishing a communications session in a communication system. In particular, it relates to a method of establishing a telephone call.
When a telephone call is made from a first telecommunications network (e.g. a fixed telecommunications network) to a second telecommunications network (e.g. a mobile telecommunications network), the first network operator charges the second network operator a fee to complete the telephone call; known as a termination charge. Since the termination charge levied by mobile network operators is higher than that levied by fixed network operators, the cost of a telephone call from a fixed network to a mobile network is higher than the cost of a telephone call from a mobile network to a fixed network. For many corporations, the cost of their office based workforce making telephone calls out to colleagues using mobile telephones (i.e. fixed network to mobile network telephone calls) is significant and cost reductions could be achieved if the direction of these calls could be reversed and therefore billed as mobile network to fixed network calls.
According to a first aspect of the present invention there is provided a method of establishing a communications session in a communications system, said communications system comprising a user terminal, a mobile terminal associated with a contact and session initiation means, said method comprising:                identifying said contact using said user terminal;        responsive to identifying said contact, transmitting contact data identifying said contact and user data associated with said user terminal from said user terminal to said session initiation means;        in dependence on and responsive to reception of said contact data, transmitting a request from said session initiation means to said mobile terminal, said request comprising said user data and requesting that said mobile terminal establishes said communications session with said user terminal in dependence on said user data.        
According to a second aspect of the present invention there is provided communication session initiation apparatus for establishing a communications session in a communications system, said communications system comprising a user terminal and a mobile terminal associated with a contact, said apparatus comprising:                data receiving means arranged in operation to receive from said user terminal, contact data identifying said contact and user data associated with said user terminal;        request transmission means arranged in operation to transmit a request to said mobile terminal in dependence on and responsive to reception of said contact data, said request comprising said user data and requesting that said mobile terminal establishes said communications session with said user terminal in dependence on said user data.        
By identifying a contact using a user terminal; and responsive to identifying said contact, transmitting contact data identifying the contact and user data associated with the user terminal from the user terminal to session initiation means; and, in dependence on and responsive to reception of the contact data, transmitting a request from the session initiation means to a mobile terminal associated with the contact, the request comprising the user data and requesting that the mobile terminal establishes a communications session with the user terminal in dependence on the user data, a communications session between a user terminal and a mobile terminal can be initiated on the user terminal but established by the mobile terminal. The direction of the communications session for billing purposes is therefore from the mobile terminal to the user terminal despite the fact that the session was initiated from the user terminal. The cost of the communications session is likely to be less than if the direction of the session was from the user terminal to the mobile terminal.
Preferably, billing for the established communications session is applied to an account associated with the mobile terminal.
In preferred embodiments, the user terminal comprises a user computer and a user telephone associated with the user computer, and the user data comprises a telephone number associated with the user telephone. In such embodiments, the method preferably further comprises the antecedent step of associating the user computer with the user telephone by storing, in a user registration database, a mapping between computer identification data identifying the user computer and telephone identification data identifying the user telephone. Thus a telephone can be associated with a computer and then the computer can be used to initiate telephone calls.
Preferably, the user data comprises the telephone identification data. Alternatively, the user registration database is accessible by the session initiation means and the user data comprises the computer identification data.
In alternative embodiments, the user terminal comprises a user telephone, the communication session comprises a telephone call and the user data comprises a telephone number associated with said user telephone. For example, the user telephone could comprise a fixed line, corded or analogue or digital cordless telephone or a mobile telephone.
In preferred embodiments, the contact data identifying the contact is stored in a contacts database accessible by the user terminal.
Preferably, the method further comprises storing said contact data in a contact registration database accessible by said session initiation means. In this way, a record of registered contacts can be created and stored in the network, which can be used to restrict access to a service operating in accordance with this method to contacts registered to use the service.
In alternative embodiments, the communication session comprises a multimedia communications session (e.g. a video call).
In preferred embodiments the mobile terminal comprises a mobile telephone. In other embodiments it comprises, for example, a personal digital assistant suitably enabled to access a communications network. In such embodiments, the contact data identifying said contact comprises the telephone number associated with the mobile telephone.
Preferably, the request further comprises a security token to be verified by the mobile terminal before responding to the request. Thus it is possible to stop someone sending spurious call setup requests to the mobile terminal.